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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Políticas territoriais e o setor elétrico no Brasil: análise dos efeitos da construção de hidrelétricas na Amazônia pelo Programa de Aceleração do Crescimento no período de 2007 a 2014 / Territorial policies and Brazilian electrical sector: analysis of the effects of the construction of hydroelectric plants in the Amazon by the Growth Acceleration Program from 2007 to 2014

Luciana Riça Mourão Borges 05 February 2018 (has links)
O estudo aqui apresentado tem como objetivo analisar o Programa de Aceleração do Crescimento (PAC), o qual tem gerado grandes transformações no Brasil, em várias escalas, modificando estruturas territoriais, políticas, econômicas e sociais. Ao estudarmos esse programa, buscamos compreender a forma como o Estado brasileiro elabora suas estratégias econômicas e políticas a apropriação, o desenvolvimento e a incorporação de territórios no país. Vivenciamos no Brasil diversas políticas territoriais de infraestrutura e de reforma agrária durante o século XX, o que ocasionou uma larga expansão da abrangência do próprio Estado no território nacional, em geral, e no território amazônico, em específico. Tais ações caracterizam, no seu contexto geral, a atual configuração brasileira, quanto ao social, econômico, político, regional e territorial. Nosso objetivo geral consistiu em analisar os efeitos do PAC no território brasileiro a partir da construção de hidrelétricas na Amazônia, considerando tais intervenções como a materialização de um projeto político dos governos Lula e Dilma, e, com isso, entender o desenvolvimentismo como estratégia de avanço e concretização das ações governamentais. Como objetivos específicos: a) Analisar as ações dos governos de Luís Inácio Lula da Silva (2002-2010) e Dilma Roussef (2011-2014) sob a perspectiva do desenvolvimentismo, identificando suas principais características políticas e administrativas; b) Analisar a construção das hidrelétricas na Amazônia dispostas como projetos do PAC 1 e 2 enquanto estudo de caso, bem como entender sua relação com o crescimento do setor elétrico nacional e o desenvolvimento econômico brasileiro; c) Identificar os principais agentes econômicos e políticos envolvidos na construção de hidrelétricas do PAC na Amazônia brasileira; d) Analisar o PAC 1 e 2 nas escalas nacional, regional e local, pela abordagem da infraestrutura energética, com a análise dos relatórios periódicos publicados pelo próprio Governo contrapostos à realização de trabalhos de campo e informações de pesquisas e movimentos sociais; e) Elaborar uma síntese territorial do PAC a partir das informações e dos dados investigados para identificar diferenciações na execução de obras de acordo com os interesses do Governo aliado às grandes empresas e agentes econômicos. Nossa metodologia consistiu na construção do instrumental analítico mobilizado durante o estudo: o levantamento bibliográfico, as etapas metodológicas, as variáveis, os indicadores, a delimitação temporal e espacial e a forma como os resultados têm sido analisados. Podemos afirmar precisamente que a tese com a qual respondemos nosso problema de pesquisa é a de que o PAC é uma política territorial. Por sua vez, essa política não atende às necessidades desse território, quer sejam sociais, econômicas e ambientais. Sendo tal, dentro dos moldes desenvolvimentistas e liberais, de outro lado beneficia (diferentemente de atender) os grupos investidores e os setores capitalistas, sobretudo e prioritariamente. / This study aims to analyze the Growth Acceleration Program (in Portuguese, PAC), which has generated large-scale development transformations in Brasil, modifying territorial, political, economic and social structures. Through this study, it was understood how the Brazilian State elaborates its economic and political strategies, as well as territories appropriation, development and incorporation. In Brazil it was experienced several territorial policies concerning infrastructure and agrarian reform during the twentieth century, which led to a significant expansion in the territorial scope, in general, and in the Amazonian territory, specifically. In general context, these actions characterize Brazilian current configuration, as far as social, economic, political, regional and territorial. The main objective consisted in analyzing PAC effects in Brazilian territory based on construction of hydroelectric plants in the Amazon, considering those interventions as the materialization of Lula and Dilma governments then understand developmentalism as a strategy for the advancement and implementation of government actions. It was formulated as specific objectives: a) To analyze, from the perspective of developmentalism, Luís Inácio Lula da Silva (2002-2010) and Dilma Roussef (2011-2014) governments actions, identifying their main political and administrative characteristics; b) To assess the construction of hydroelectric plants in the Amazon as PAC 1 and 2 projects as case study and to understand its relation with the growth of the national electrical sector and the Brazilian economic development; c) To identify the main economic and political agents involved in the construction of PAC hydroelectric plants in the Brazilian Amazon; d) To evaluate PAC 1 and 2 at the local, state and national levels, under energy infrastructure bias, analyzing periodic reports published by the Government against the fieldwork and information of research and social movements; e) To elaborate a PAC territorial synthesis grounded on the information and data investigated to identify the differences in the execution of works in accordance with the interests of the Government allied to large companies and economic agents. The methodology employed in this work sought to build the analytical instruments mobilized during the study: bibliographic survey, the methodological steps, the variables, the indicators, temporal and spatial delimitations and how results have been analyzed. It can be precisely said that the thesis with which we responded the research problem is that PAC is a territorial policy. In turn, this policy does not meet the needs of this territory, which are social, economic and environmental. Therefore, within the developmental and liberal molds, overall it benefits (unlike attending) the investing groups and the capitalist sectors, especially and, as a matter of priority.
72

Estudos de repotenciação de usinas hidrelétricas por meio da motorização de poços vazios existentes / Repotentialization studies of hydroelectric power plants through motorization of existing empty pits

Lemos, Hermann Friedenberg de, 1958- 11 March 2014 (has links)
Orientador: Sérgio Valdir Bajay / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-26T09:00:06Z (GMT). No. of bitstreams: 1 Lemos_HermannFriedenbergde_M.pdf: 3871312 bytes, checksum: 36fc898180d77fe9d34caeeec2e8e480 (MD5) Previous issue date: 2014 / Resumo: Este trabalho analisa a viabilidade técnica e econômica da motorização de poços vazios previamente escavados e concretados, existentes em dez usinas hidrelétricas brasileiras de médio e grande porte. O objetivo é acrescentar potência instalada e disponibilizar energia nova para atendimento ao horário de ponta de carga do Sistema Interligado Nacional (SIN). Foram coletados junto ao Centro Nacional de Operação do Sistema Elétrico (CNOS), dados operacionais hidroenergéticos consolidados ao longo de dez anos, referentes às vazões turbinada e vertida, produtividade, potência média produzida e potência média vertida. Os dados operacionais foram utilizados nas equações criadas para dimensionar a quantidade de poços a motorizar e os respectivos acréscimos de potência. Simulações sistêmicas foram realizadas junto ao Centro de Pesquisas de Energia Elétrica (CEPEL), para estimar os ganhos de energia provenientes dos acréscimos de potência, utilizando os modelos de simulação daquele Centro. Fluxos de caixa, compostos pelas despesas necessárias ao investimento e pelas receitas da venda da nova energia, proporcionaram a análise da viabilidade econômica. Os resultados encontrados mostram que somente a remuneração do ganho de energia resultante da motorização adicional não viabiliza economicamente a instalação de unidades geradoras na maioria dos poços vazios disponíveis nas usinas hidrelétricas analisadas. As principais conclusões sinalizam para a obtenção de soluções econômica e regulatória que fomentem a viabilização da motorização dos poços vazios sob a ótica do mercado comercializador de energia elétrica, incluindo a valoração do acréscimo de potência instalada / Abstract: This work examines the technical and economic feasibility of inserting power generation sets in empty pits previously excavated and concreted in ten medium and large Brazilian hydroelectric power plants. The goal is to add new installed capacity and energy available to meet the peak hour load of the National Interconnected System. Hydropower operational data consolidated over ten years, related to the generation and no generation flows, productivity, average power produced and poured average power, were collected from the National Center Operation of Electrical System. The operational data were used in equations created to scale the number of pits to be motorized and its power increases. Systemic simulations were performed by the Center for Electric Power Research to estimate the energy gains arising from increased power, using simulation models that Center. Cash flows with investment expenditures and revenues from the sale of new energy provided the analysis of the economic viability. The results show that only the compensation of the energy gain resulting from the additional motorization not economically feasible to install generating units in most empty pits available in hydro plants analyzed. The main conclusions point to the attainment of economic and regulatory solutions that foster the viability of empty pits¿ motorization from the perspective of wholesale electricity market, including the remuneration of the new installed capacity / Mestrado / Planejamento de Sistemas Energeticos / Mestre em Planejamento de Sistemas Energéticos
73

An adaptive impact monitoring and management strategy for resource development projects

Dushnisky, Kelvin Paul Michael 11 1900 (has links)
This thesis advances a conceptual model of adaptive impact monitoring that is designed to overcome many of the criticisms plaguing conventional monitoring strategies. The potential for applying the adaptive model is demonstrated for the Peace River Site C dam proposed for northeastern British Columbia. Environmental impact assessment (EIA) has progressed considerably from its early biophysical orientation to a more comprehensive, interdisciplinary process concerned with the breadth of environmental and socio-economic impacts of development. Impact monitoring, an essential EIA component, has also progressed but in a less innovative fashion. Consequently, conventional monitoring strategies often contain significant deficiencies including insufficient use of past experience, poor monitoring design, and failure to recognize the learning opportunity offered by each project. Adaptive impact monitoring offers significant advantages over traditional strategies. An adaptive strategy is based on a series of impact hypotheses established and tested by an interdisciplinary design team and has two fundamental stages: design and evaluation. A review of the potential environmental impacts of hydroelectric production indicates that the reservoir impact paradigm is beginning to provide a comprehensive basis for assessing development effects. Although the Site C EIA adequately reflects the reservoir impact paradigm, it has three significant weaknesses. First, the potential impacts on downstream ecology and distant downstream users are ill-considered. Second, the potential for increased Site C fisheries parasitism is neglected. Finally, estimates of maximum sustainable yield for the Site C reservoir and Peace River fisheries are unreliable. While opportunities for future impact monitoring were recognized through the Site C panel hearings, they lacked flexibility. The potential impacts on downstream water temperature and fisheries resources are used to illustrate the applicability of the adaptive strategy and the advantages derived from collecting only relevant, statistically credible data to permit testing impact hypotheses in a cost-effective manner. On the basis of these findings, six major policy recommendations are provided for improving the effectiveness of impact monitoring and management for future resource developments. / Graduate and Postdoctoral Studies / Graduate
74

Abordagem lexicográfica na otimização da operação de usinas hidrelétricas / Lexicographic approach to optimize the short-term scheduling of hydroelectric power plants

Fernandes, Jéssica Pillon Torralba, 1985- 05 August 2015 (has links)
Orientadores: Ieda Geriberto Hidalgo, Paulo de Barros Correia / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-27T18:22:11Z (GMT). No. of bitstreams: 1 Fernandes_JessicaPillonTorralba_D.pdf: 6009989 bytes, checksum: a3f55f4b7f91827762cdfb4e83ebcf4c (MD5) Previous issue date: 2015 / Resumo: Em busca do desenvolvimento sustentável, a atividade de produção de energia iniciou o século XXI com foco em dois temas: eficiência energética e utilização de fontes de energia renováveis. O Brasil é um país privilegiado em termos de disponibilidade de recursos naturais para a geração de energia, principalmente através da água. Apesar da evolução de outras fontes renováveis de energia, como a biomassa e a eólica, é previsto um aumento da utilização de energia hidráulica na geração de eletricidade de forma sustentável. Para acompanhar esse aumento, existe a necessidade de expandir a oferta de energia através da instalação de novas usinas hidrelétricas e/ou otimização da operação das usinas hidrelétricas existentes. Neste contexto, esta tese apresenta uma metodologia para resolver o problema de despacho dinâmico de máquinas e geração com horizonte diário e discretização horária. Ela baseia-se na Programação por Metas Lexicográficas, utilizando Algoritmo Genético e Strength Pareto Evolutionary Algorithm. A formulação matemática do problema possui dois objetivos conflitantes. O primeiro consiste em maximizar a geração líquida da usina ao longo do dia. O segundo visa minimizar o número de partidas e paradas das unidades geradoras. A resolução é executada em duas etapas. Na Etapa 1, o Algoritmo Genético é utilizado para resolver o problema estático para cada hora. Na Etapa 2, Algoritmo Genético e Strength Pareto Evolutionary Algorithm são empregados para solucionar o problema dinâmico ao longo de um dia. As soluções encontradas são analisadas através da construção de uma curva de trade-offs. Os estudos de casos são realizados com as usinas Jupiá e Porto Primavera ,que pertencem ao Sistema Interligado Nacional. Os resultados mostram que a metodologia proposta apresenta soluções eficientes e econômicas para a programação diária de usinas hidrelétricas / Abstract: In pursuit of the sustainable development, the energy production activity began the 21st century with focus on two themes: energy efficiency and use of renewable energy sources. Brazil is a privileged country in terms of availability of natural resources to energy production, mainly through water. Despite the development of other renewable energy sources, such as biomass and wind power, hydro energy is expected to increase in the electricity generation in a sustainable way. To keep this growing, there is a need to increase the supply of energy by installing new hydroelectric plants and/or optimizing the operation of existing ones. In this context, this thesis presents a methodology to solve the dynamic dispatch problem of units and generation with a daily horizon and hourly discretization. It is based on Lexicographic Goal Programming using Genetic Algorithm and Strength Pareto Evolutionary Algorithm. The mathematical formulation of the problem has two conflicting goals. The first consists of maximizing the electric power output the plant throughout the day. The second aims to minimize the number of start-ups and shut-downs of the generating units. The resolution is divided in two steps. In Step 1, Genetic Algorithm is used to solve the static problem for each hour. Phase 2 employs Genetic Algorithm and Strength Pareto Evolutionary Algorithm to solve the dynamic problem throughout the day. The solutions are analyzed by building a trade-offs curve. The case studies are carried out with Jupiá and Porto Primavera hydroelectric power plants that belong to the National Interconnected System. The results show that the proposed methodology provides efficient and economic solutions for the daily operation of hydroelectric power plants / Doutorado / Planejamento de Sistemas Energeticos / Doutora em Planejamento de Sistemas Energéticos
75

A privatização e descentralização do setor elétrico nacional frente à política ambiental brasileira: uma abordagem sociológica do caso das Pequenas Centrais Hidrelétricas (PCHs) / The national electric sector privatization and decentralization in relation to the Brazilian environmental policy: a sociological approach of the small hydroelectric power plants case

Patrícia Aparecida Pereira Souza 16 September 2004 (has links)
A onda de recessão econômica e de desaceleração do crescimento da década de 80, aliada à crise política e financeira vivenciada pelos Estados Nacionais na A.L., abriu terreno para que concepções neoliberais permeassem as decisões ligadas aos investimentos necessários em infra-estrutura. O Brasil, do Governo Collor ao FHC (1990 à 2002), seguiu esta orientação e, por meio dela, permitiu que vários segmentos dos serviços essenciais se tornassem passíveis de privatização e descentralização, dentre eles, o setor elétrico que foi reestruturado. Dado o contexto supra, este estudo visa analisar, sob um prisma sociológico e da geografia humana, o ressurgimento das pequenas centrais hidrelétricas no cenário nacional, intentando dar pistas da efetividade da política ambiental brasileira quando da implantação e recuperação destas usinas. Trata-se de examinar quais mecanismos político-institucionais permitem que o bem público, representado pelos recursos hídricos, possa ser apropriado para responder às necessidades de natureza privada, e como as necessidades sócio-ambientais imbricadas são contempladas nesse processo. É apresentado um estudo de caso para trazer à tona, por um micro recorte, a implantação de pequenos aproveitamentos hidrelétricos no qual a necessidade expansionista do setor reitera um padrão de excludência social e pouca efetividade decisória dos agentes sociais afetados. / The 80\'s wave of economic recession and decelerated development, allied to political and financial crises experienced by Latin American National States, opened field to a spread-out of classic conceptions through decisions connected to necessary infra-structure investments. Brazil followed this orientation, from Collor to FHC (1990 to 2002), and allowed many essential service segments to become liable of privatization and decentralization, among them, the electric sector, which was re-structured. Considering this context, this study aims to analyze under sociological and human geographical viewpoints, the resurgence of Small Hydroelectric Power Plants on the national scenery, intending to give cues of the Brazilian environmental policy effectiveness, by the time of these plants implantation and recovery. It concerns of examining which are the political-institutional mechanisms that allow the public welfare, represented by hydrous resources, to be convenient to private nature demands, and how the involved social-environmental demands are analyzed on this process. A case study is presented in order to bring-up, through a short brief, the implantation of small hydroelectric plants, where the growing necessity of the sector, reaffirms a pattern of social exclusion and few conclusive effectiveness of the affected social agents.
76

Power Failures: Engineers and the Litani River, 1918–1978

Lawson, Owain January 2021 (has links)
This dissertation is a history of efforts to develop the Litani River in Lebanon. Under French rule (1920–43), development projects shaped an unequal distribution of infrastructure that privileged Christian and urban regions. A cohort of nationalist Lebanese engineers advocated developing the Litani River, in Lebanon’s Shi‘a-majority southwest, as a means to foster national unity by resolving inequalities among Lebanon’s religious communities. The resulting Litani project (1955–65) was Lebanon’s first grand-scale hydroelectric project. The United States, France, and the World Bank made the project central to their respective strategies in the decolonizing Middle East. Lebanese engineers competed and collaborated with European and American experts to design infrastructure that connected the Litani, and Lebanon’s hinterland, with the capital, Beirut. Economists, religious leaders, farmers, and communists debated infrastructure designs in Beirut’s bourgeoning public sphere. The completed infrastructure generated electricity for Beirut’s consumers by extracting water from the impoverished rural margins. The World Bank deemed the project a qualified success as an investment. But most in Lebanon considered it a monumental failure because the infrastructure did not meet urgent needs. Rather, the infrastructure materialized preexisting inequalities between Beirut and its peripheries, which provided a visible injustice that a rural Shi‘i political-religious movement mobilized to demand equal rights. Unlike familiar histories of development in which rural communities resist state intrusion, in Lebanon, rural actors and engineers sought to build a larger and more equitable state by constructing socially just infrastructure.
77

Modeli rizika za procenu nivoa vibracija tehničkih sistema / Models of risk for assessment of vibration levels of technical systems

Jurić Slobodan 11 September 2018 (has links)
<p style="text-align: justify;">Istraživanje modela rizika predstavlja stalnu&nbsp;proveru parametara vibracija sistema, na osnovu&nbsp;kojih se može prognozirati vreme zamene&nbsp;komponenata pre nego &scaron;to dođe do njihovih&nbsp;otkaza. Model se zasniva na stalnom praćenju&nbsp;parametara stanja u cilju eliminacije slabih mesta&nbsp;na tehničkom sistemu. Na taj način će biti&nbsp;ustanovljeni modeli za predviđanje i sprečavanje&nbsp;otkaza u radu tehničkog sistema. Karakteristika&nbsp;ovog modela je u neprekidnom praćenju stanja&nbsp;tehničkog sistema u procesu eksploatacije i&nbsp;iznalaženje uporednog modela za procenu rizika,&nbsp;prema ISO standardima. Istraživanje je imalo za<br />cilj da se izvr&scaron;i: procena dinamičkog stanja,&nbsp;osetljivosti i sklonosti rotirajućih elemenata<br />hidro-elektrane (HE) ka debalansu, kao i procenu&nbsp;sigurnosti funkcionisanja vratila i rotora<br />turbinskog dela uređaja HE sa aspekta&nbsp;minimalnog rizika od pojave zastoja.</p> / <p>Research into risk models is a constant check of&nbsp;the system&#39;s vibration parameters, based on&nbsp;which the time of replacing components can be&nbsp;predicted before their failure occurs. The model&nbsp;is based on continuous monitoring of state&nbsp;parameters in order to eliminate weak spots in the&nbsp;technical system. In this way, models will be&nbsp;established for predicting and preventing failure&nbsp;in the work, technical system. The characteristic<br />of this model is the continuous monitoring of the&nbsp;state of the technical system in the exploitation&nbsp;process and the finding of a comparative risk&nbsp;assessment model, according to ISO standards.&nbsp;The aim of the research was to evaluate the&nbsp;dynamic state, sensitivity and tendency of the&nbsp;rotating elements of the hydroelectric power<br />plant (HE), to the imbalance, as well as to assess&nbsp;the safety of the functioning of the shaft and rotor&nbsp;turbine part of the HE unit from the aspect of&nbsp;minimal risk of occurrence of delays.</p>
78

Edith Irvine: Her Life and Photography

Plunkett, Wilma Marie 01 June 1989 (has links) (PDF)
ln mid-1988, Brigham Young University received a high-quality collection of photographic glass plates made by Edith Irvine at the tum of the century. The plates, her camera and other photographic equipment, and miscellaneous publications were donated to BYU by her nephew, Jim Irvine. When the plates arrived and the Archives Photolab had them proofed, we realized thal not only were the San Francisco earthquake/ fire and other areas of California history recorded, but we had, in fact, the work of an outstanding photographer. As we compared the proofs with the work of other photographers who handled similar subjects, we called on faculty members qualified to judge her work. All were unstinting in their praise. As our Archives Curator, Dennis Rowley, looked at them, he said, "I've never seen a sel of photographs create a mood like these do." The more I worked with them, the greater my need to do more than just process and preserve. As I discussed the collection with the faculty members, it became evident to me that I should make a change in my graduate program. I was determined to learn more about the photographer. The collection of photographs can be viewed in the Edith Irvine Collection.
79

Methods and cost of developing farm water power

Wallace, Harry Moore January 1926 (has links)
no abstract provided by author / Master of Science
80

Development ethics and the Canadian North : a case study analysis of the Churchill-Nelson Rivers Hydro Diversion Project

Friesen, Wilbert J. January 1999 (has links)
This thesis argues that economic development, in both theory and practice, is inevitably based on moral questions. These questions have been explored in recent years by "development ethicists," a multidisciplinary group of scholars and practitioners committed to evaluating the policy implications of economic development. Chapter 1 engages this body of literature, arguing that the capability ethic articulated by Amartya Sen and Martha Nussbaum can provide a valuable ethical framework for evaluating economic development in the Canadian north. Their approach is considered in conjunction with other ethical proposals, and, in particular, how theological insights provide an additional dimension for a more comprehensive development ethic. / Chapter 2 investigates the ethical assumptions in the theories and models of economic development proposed for the Canadian north, and how public policy based on these theories and models has infringed on the claims and aspirations of Aboriginal peoples. The chapter then shifts from the larger Canadian context to Manitoba, and explores the story of how two hydro development projects impacted several Aboriginal communities. / This story provides the context for understanding why four church denominations became involved in defending the rights and aims of five Aboriginal communities in northern Manitoba. Chapter 3 examines the moral vision of the four Christian churches and their rationale for sponsoring four days of public hearings on the Churchill-Nelson Rivers hydro diversion project. The public hearings provide an opportunity to analyse how development affects the lives of a people group when it is thrust upon them without consideration of their economic, cultural, and social value systems. / The final chapter examines the issue of the loss of cultural identity for Aboriginal communities as economic development occurs. A major issue pertaining to the loss of cultural identity is whether a development ethic should be based on a universal ethic, or on local traditions, for example, the traditions of the five Aboriginal communities in northern Manitoba. The efforts of the Interchurch Task Force are investigated as a particular type of response to these issues.

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